This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A173191 #16 Aug 29 2022 04:42:08
%S A173191 1,63,2268,61236,1377810,27280638,491051484,8207574804,129269303163,
%T A173191 1939039547445,27922169483208,388371993720984,5243021915233284,
%U A173191 68965903654222428,886704475554288360,11172476391984033336,138259395350802412533,1683511461036241140843
%N A173191 a(n) = binomial(n + 6, 6)*9^n.
%C A173191 Number of n-permutations (n>=6) of 10 objects p, r, q, u, v, w, z, x, y, z with repetition allowed, containing exactly six (6) u's.
%H A173191 Vincenzo Librandi, <a href="/A173191/b173191.txt">Table of n, a(n) for n = 0..400</a>
%H A173191 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (63,-1701,25515,-229635,1240029,-3720087,4782969).
%F A173191 a(n) = C(n + 6, 6)*9^n.
%F A173191 From _Amiram Eldar_, Aug 29 2022: (Start)
%F A173191 Sum_{n>=0} 1/a(n) = 1042074/5 - 1769472*log(9/8).
%F A173191 Sum_{n>=0} (-1)^n/a(n) = 5400000*log(10/9) - 2844729/5. (End)
%p A173191 A173191:=n->binomial(n+6,6)*9^n: seq(A173191(n), n=0..25); # _Wesley Ivan Hurt_, Jul 24 2017
%t A173191 Table[Binomial[n + 6, 6]*9^n, {n, 0, 20}]
%o A173191 (Magma) [Binomial(n+6, 6)*9^n: n in [0..20]]; // _Vincenzo Librandi_, Oct 13 2011
%Y A173191 Cf. A081139, A173000, A173187, A173188.
%K A173191 nonn,easy
%O A173191 0,2
%A A173191 _Zerinvary Lajos_, Feb 12 2010